The brigade was the first major United States Army ground formation deployed in Vietnam, serving there from 1965 to 1971 and losing almost 1,800 soldiers. Noted for its roles in Operation Hump and Operation Junction City, the 173rd is best known for the Battle of Dak To, where it suffered heavy casualties in close combat with North Vietnamese forces. Brigade members received over 7,700 decorations, including more than 6,000 Purple Hearts.

Ayahuasca (usually pronounced /ˌaɪjəˈwæskə/ or /ˌaɪjəˈwaːskə/), also commonly called yagé (/jaːˈheɪ/), is an entheogenic brew made out of Banisteriopsis caapi vine, often in combination with various other plants. The brew is used as a traditional spiritual medicine in ceremonies among the Indigenous peoples of Amazonian Peru, many of whom say that they received the instructions in its use directly from the plants and plant spirits themselves.
Ayahuasca was first described outside of Indigenous communities in the early 1950s by Harvard ethnobotanist Richard Evans Schultes, who became aware of the Native communities who use it for divinatory and healing purposes. It has been reported that some effects can be felt from consuming the caapi vine alone, but that DMT-containing plants (such as Psychotria) remain inactive when drunk as a brew without a source of monoamine oxidase inhibitor (MAOI) such as B. caapi.[1] It can be mixed with the leaves of Chacruna or Chagropanga, dimethyltryptamine (DMT)-containing plant species, and is known by a number of different names (see below).[2]